The present invention relates generally to satellite switching systems, and more particularly, to an active switch matrix subsystem for routing communication channels through a satellite payload.
The assignee of the present invention manufactures communication satellites that operate to receive and retransmit telephone and data communication signals between users. Customers that utilize assigned communication channels on such satellites have expressed a desire to have a very fast payload switch matrix for reconfiguring their payload on the order of millions of cycles per mission.
It would therefore be desirable to have a switching system for use in satellites that permits rapid reconfiguration of the satellite payload. Accordingly, it is an objective of the present invention to provide for an active switch matrix subsystem for routing communication channels through a satellite payload.
To accomplish the above and other objectives, the present invention provides for switching apparatus comprising active switch matrix apparatus or subsystem that may be used in a satellite communications system or payload that provides the ability to reconfigure communication channels of the satellite payload in only a few milliseconds. The switching apparatus has redundancy that provides for a high probability of success during the lifetime of the satellite. One aspect of the switching apparatus is that it provides increased flexibility and speed at which the payload may be reconfigured.
In general, the switching apparatus comprises first and second switch matrices. The switch matrices each comprise a plurality of power dividers that each comprise a plurality of controllable switches, a plurality of power combiners coupled to corresponding outputs of each of the plurality of power dividers, a plurality of amplifiers respectively coupled to outputs of the plurality of power combiners, and a plurality of controllable output switches coupled to outputs of the plurality of amplifiers that are selectively enabled to provide outputs of the switching apparatus. A switch matrix controller is coupled to the controllable switches and controllable output switches for selectively switching the switches to provide communication paths through the apparatus. A DC/DC converter provides DC power to the switch matrix controller and switch matrices.
To provide for additional redundancy, a backup switch matrix controller is coupled to the controllable switches and controllable output switches for selectively switching the switches to provide communication paths through the apparatus. A second DC/DC converter provides DC power to the second switch matrix controller and switch matrix assembly when it is in operation.
More specifically, the active switch matrix apparatus is comprised of two switch matrices, one for each polarization (horizontal and vertical). Each of the switch matrices has redundancy, including redundant paths through power dividers, power combiners and amplifiers to outputs of the apparatus. Each of the switch matrices are coupled to redundant DC/DC converters and switch matrix controllers. The first and second switch matrices respectively process a plurality of beams having first and second polarization states. Each switch matrix comprises a plurality of power dividers that respectfully process the plurality of beams and divides power derived from each of the beams.
Each switch matrix comprises a plurality of power dividers that are each coupled to a plurality of controllable switches, and a plurality of power combiners whose respective inputs are coupled to receive corresponding outputs of the plurality of controllable switches of each of the plurality of power dividers. A plurality of amplifiers are respectively coupled to outputs of the plurality of power combiners, and a plurality of controllable output switches coupled to outputs of the plurality of amplifiers that are selectively enabled to provide outputs of the active switch matrix apparatus.
First and second redundant switch matrix controllers are coupled to the plurality of controllable switches and to the plurality of pairs of controllable output switches for selectively switching the switches to route the beams through the apparatus. First and second redundant DC/DC converters are coupled to the first switch matrix controller that provide DC power to an active switch matrix controller and to the switch matrix assemblies.